1. Technical Field
The present invention relates to a drive circuit which generates a drive control signal based on a rotational state signal of a sine waveform which indicates a rotational state of a motor.
2. Background Art
Recently, for a vibration function equipped in portable phones or game machines, a position detecting circuit which uses a Hall element is used for detecting a position of a vibration element.
When a magnet is employed as a rotor and a coil is employed as a stator, the Hall element detects a position of the rotor, and a drive circuit supplies a current to the coil based on a detection result of the Hall element.
There exists a demand for minimizing power consumption in an electronic device. This demand is particularly strong for a portable device or the like which is driven by a battery. In a vibration motor which has the vibration element in the related art, currents around 0° and 180° do not significantly contribute to the driving of the motor. In consideration of this, an electricity application method which cuts the currents around 0° and 180° of the motor drive current has been proposed. For example, an electricity application method which cuts electricity application for 30° around 0° and 180° is known as a 150°-electricity application.
In order to execute such 150°-electricity application, a circuit for generating signals for the 150°-electricity application is required. There also is a demand for simplifying this circuit.